Adenine-derived carbon dots for the chemosensing of hypochlorite based on fluorescence enhancement

Abstract

Abstract A novel fluorescent chemosensing strategy on the detection and determination of hypochlorite (ClO−) based on fluorescence enhancement was reported. In this work, nitrogen-doped carbon dots (N-CDs) were prepared via one-step hydrothermal conversion of nitrogen-rich adenine and ethylenediamine. The N-CDs solution showed excitation-dependent characteristic and displayed green fluorescence (535\xa0nm) when excited by blue light (480\xa0nm). The fluorescence intensity was linearly enhanced with the concentration of ClO− increasing in the range of 0.01–1\xa0mM, and the limit of detection was calculated to be 0.82\xa0μM. Other than the common oxidation of the N-CDs surface by ClO−, spectra change stemmed mainly from aggregation-induced enhanced emission (AIEE), including π-π staking and J-aggregation, which together induced red-shift absorption band and effective fluorescence enhancement. Based on the good sensitivity to ClO−, the N-CDs probe also underwent real sample assay and gave relatively reliable recoveries of ClO− contained in various water samples. In addition, the N-CDs showed excellent anti-interference in the selectivity test and exhibited good stability in complex solution environment with different pH values or ion strengths. In view of the results, the N-CDs sensing probe has impressive sensitivity and selectivity on ClO− determination and possesses good potential on bioimaging applications.